Spark-plug



W. 0. OLSN.

'SPARK PLUG.

APPLICATION FILED MAY 20, i918. 1,354,126, pl-tentedsept. 28,1920.

y vention will UNITED STATES -WILLIAM O. OLSON, OF CHICAGO, ILLINOIS, ASSIGNOR,

BY' MESNE ASSIGNMENTS, To

THE ABC-O MANUFACTURING CO., INC.,"OF CHICAGO,0 ILLINOIS, A CORPORATION or ILLINOIS.

SPARK-PLUG.-

' To all 'w hom t may coiwer'n.'

Be it known that I, WILLIAM O. OLsoN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Spark-Plugs, of which the following is a speciiicatio.. l Y

This invention relates to spark plu for internal combustion engines and has or its primary object the provision of a spark plug 'embodying electrode terminals adapted to be maintainedin a highl heated or substantially incandescent con ition during'use whereby any 'oil which contacts with the terminals is immediately ignited and burned so that the terminals are maintained clear permanently.

A further object of my invention Vis the provision of a novel construction including a packing ring between the shell and core vof a spark plug which insures a permanently tight joint.

Further obgects and advantages of my in e apparent as it is better understood by reference to the followin speci-v cation when read in connection with the accompanying drawing illustrating the preferred embodimentlthereof, in which Figure 1F isa longitudinal section through a spark plugv according to my invention;

Fig. 2 is an elevation o f a core showing the packing ring in place, and

Fig. 3 is a plan view of the packing ring. Referring to the drawing, 5 indicates a shell having a reduced'threaded neck 6 adapted for insertion in the head of internal combustion lengine cylinders. The shell 5 is provided with a shoulder or seat 7 upon which a gasket 8-.rests. A corresponding shoulder 9 `of ian insulating core 4 1() restsi upon the v asket 8. The core 10 isr held in assembler? y 5 by means of a' threaded sleeve 11, the

lo'wer edge of which engages a paokting ring 12. This packing ring is ofaparticular form and'is intended and adapte to maintain'a thoroughly tight joint even when frequently .removed and replaced. It com-` prises .a ring of annealed -brass having a flat face 13 adapted to be en aged by the lower edge of the sleeve11 an a depending re1atively. .thin lip, 14 which conforms to i' a curved shoulder 15 on the core 10.' As the ring `12 is -forced against. the shoulder by the sleeve 11, the lip 14 follows the curva" lthe electrode without subjecting the core to relation. with the shell vprovide a -con ASpeciiicationot Letters Patent. Patented Sept. 28, 1920. Application led Hay 20, 1918. Serial No. 235,586.

closely to the curvature ofthe shoulder 13 thus 1nsuring a permanently tight joint.-

The core l0 is provided with a central opening through which a central electrode 16 extends and which is somewhat larg'ei.` than the electrode to permit expansion of pressure. A flange 17 near the lower end of the electrode 16 en ages a gasket y18 held in a recess in the enc? of the core 10. The electrode 16 is held in assembled relationv with the'core 10 by means of a nut 19 between which and the end of'the core 10 a spring washer 20, a fiat washer 21 and an asbestos washer 22 are disposed. A cap 23v is threadedly mounted upon the electrode 16 covering the nut 19 and the washers therebeneath and a terminal nut 24 is mounted above the cap 23 on the electrode. A recess 24 in the end of the core is adapted to receive ia strip of asbestos yarn 25 which when compressed enters the threads in and centers the electrode and holds itin' assembled relation with the core..

The lower' end ofthe electrode 16 is rovided with a flattened terminal 25 rigidly connected to the. end of the electrode and' provided'with a sharpened edge 26 of considerable length. This terminal is constructed ofmetalhaving relatively low heat conductivity and which is not easily oxi- .the two terminals is a thin flattened sheet which insures firing of the charge within the engine cylinders and the maintenance of the terminal 25 in a highl heated conditiorn 'It should be understoo that the electrode terminal Yin m spark plug -is designedto dy'tion quite contrary to that generally desired. I have discovered that in many modern vinternal combustion engines, owingv to clearancejbetween the pistons and Acylinders and the dilution of .the lubricating oil, bycondensed combustible vapor, a considerablel amount of oil reaches the interiors of the cylinders and is deposited on the electrode terminals of the spark plugs when it carbonizes and prevents proper sparking. I have discovered that this diiculty may be overcome entirely by providing a spark plug in which the terminals are maintained in a highly heated or substantially incandenscent condition, and

, I have found that the structure described i understood that plug having marked and desirable advan` herein is best adapted to accomplish this purpose.- i

From the foregoing it will be readil have perfected a spar tages over spark plugs commonly employed ein. internal combustion engines, and that inbeforedescribed being merely a preferred embodiment thereof.

A s ark lug having a straight electrode theret roug and provided at its lower end with an axially dispos d flattened terminal of non-oxidizing meta having a relativelylow heat conductivity, the sparking end of said terminal being arranged transversely of said electrode and extended in length greater than the transverse diameter of f said electrode and greater than the width, of the terminal back of said'sparking end,v and another electrode having its terminal arranged beneath and parallel with said sparking end.

WILLI'AM O.v OLSON. f

Witnesses:

ERNEST H. MERCHANT, M. A. KIDDIE. 

